Personal information management programs - PIMs for short - are like shoes. Once you find one that fits, you'll never want to give it up. So take some care to find the PIM that fits you best.

PIMs are generally multifunctional. They do a lot of little, puttery things for you. They come in three broad categories. The first manages text and data contained in computer files. A second group handles phone calls and keeps track of telephone contacts. A third focuses on appointment scheduling.This week we'll look at file managers. (All but one work only on IBM compatibles.) In future weeks we'll review software in the other two groups.

Magellan is a powerful information cruncher. It organizes files and their data, whether on one or several computer disks.

Hitting F9 activates Magellan's Explore feature. It searches files for any key word or phrase you want. It lists all the files containing those words by descending number of hits. If you ask it to find all your files with January 31 typed somewhere in them, it tops the list with the file that says `January 31' the most times.

Magellan lets you use fuzzy searches. For instance, searching for compu? will turn up files containing compute, computer, computers, computerization and so forth.

You can also use Boolean logic. And, or and not are terms in Boolean logic. You can tell Magellan (or any other program that uses Boolean logic) to find files containing APPLE and PEAR or APPLE or PEAR or APPLE not PEAR.

`And' finds files where both words are present. `Or' finds files where either or both are present. `Not' only lists files with APPLE in them that don't contain the word PEAR.

Magellan works fastest if you first use its file indexing utility. (Most file searching programs now use indexing.) Indexing is computer jargon for a process that presorts all the words and numbers (usually alphabetically) in a whole bunch of files. For each file, it stores the list as an index. When you ask it to find something, it scans the index and finds your data Whiz Bang Fast.

Magellan also helps manage files. It sorts and lists them alphabetically or by size or creation date or whatever you like. It can also compress (and, fortunately, decompress) files.

Compression is a great way of saving disk space while keeping seldom-used files on your disk. Compressed, they generally occupy half the space of uncompressed files, yet none of your data is lost. It's like taking the air out of a tire. It's still a tire, even if you can't use it until you pump back all the air.

If you had Magellan index a file before compression, the program can still search it. If it's the file you're looking for, just decompress to resurrect it. The program keeps indexes even for files you remove from your hard disk to backup disks or tapes.

It lists for $139 and is sold by most local computer stores. ZyIndex is just a text searcher. It only searches files you've preindexed. It's worth buying if you're constantly looking for information in the same large files. For impromptu searching, Magellan's better. ZyIndex costs $295 and up and is made by ZyLab; phone (800) 544-6339.

IZE is a sleeper. It combines the better qualities of Magellan and ZyIndex. We've used it for years, but the company's advertising was always sluggish. They've just reorganized to change all that.

IZE has a unique approach to information handling that makes it extremely useful in data-intensive offices: You can teach it to recognize the beginning and ending of large chunks of text.

We use IZE to compile easily searchable files full of data about software. Each raw file may contain data about dozens of different programs: name, maker, phone, address, technical specifications, operating systems it can run under, vendor-supplied summaries of the program's strong points and our own summaries of weak points.

We taught IZE to automatically recognize the beginning and ending of each program's review and the set of key words by which we want it to be specially indexed. You can supply IZE with key words or let it seek out its own.

During the retrieval process, IZE generates an outline based on the key words plus other data it sifts from each program review. From the outline, we can often zero in on a small collection of reviews that exactly meet our current needs. It saves us from having to manually read through every review that in some way matches our key word.

IZE costs $495 and is made by Persoft (608-273-4357). It, too, is not very good for off-the-cuff disk searching. Magellan's much better. So is Norton's handy TS utility.

TS (Text Search) is sold as part of Norton Utilities. We often use it to answer our reader mail.

Many readers write to ask where to buy something we've mentioned in the column. We usually include the maker's name and phone number in our columns, but some subscriber newspapers take them out. Since the data's there in our file, we can call up TS and tell it what directory to search and what word or phrase to look for.

As TS finds a file with the right program named in it, it shows the name in context onscreen. It also names the file so we can call it up. But we rarely need to do that. One of TS's hits usually shows the price and maker's phone number within the few lines displayed onscreen.

If Norton Utilities is new to you, find a store that stocks it. Its collection of several dozen programs does everything from salvaging accidentally erased files and timing events on your computer to searching for hidden or lost data. One use generally pays back your investment since it costs only $179 for IBM compatibles, $129 for the Macintosh.