(MONEY Magazine) – Some 110 or so national Internet service providers (ISPs) would like to be your gateway to cyberspace (with another 4,900 regional players at the fringes), and what largely separates one from the other is what you pay every month and the ease of making a connection. Once you're on the Internet, your favorite Websites look the same no matter how you got there.

Four months ago, we named Earthlink Network the best all-around ISP deal ("Super Deals," July), largely because of its reliable connection. Since then, the service has attracted some 200,000 new members and as of August no longer gets the top grade in Inverse Network Technologies' monthly call-failure survey. At $19.95 a month--which is the going rate for unlimited time online--Earthlink (800-395-8425; www.earthlink.net) is still a good value--but not necessarily the best deal for everyone.

Before you pick an ISP, ask yourself: Do you primarily go online to read and send e-mail, or do you want to track your portfolio all day? Are you a frequent traveler who needs an ISP available anywhere, or do you always surf from home?

Another consideration is whether the ISP has a nearby local access number. If not, you could add phone charges of 10[cents] a minute or so to your online tab. If you call your ISP's toll-free number to cut your phone bill, you could pay a surcharge of up to $5.95 an hour.

Finally, you may want to think twice before you sign up for a temporary deal or pick an up-and-comer that's likely to become a takeover target. Hopping ISPs isn't as simple as changing your long-distance service. Just ask anyone who's had to change an e-mail address or reconfigure a computer to support new ISP software. With that in mind, here are top choices for four types of Net users.

All you use is mail. If your main online activity is exchanging e-mail with your kids, you hardly need a $19.95-a-month unlimited Internet access plan. America Online (800-540-9449; www.aol.com), whose notorious $21.95-a-month fee for unlimited time online is among the priciest out there, has a good but less publicized deal for anyone who checks e-mail only once or twice a week: For $9.95 a month, you get five hours of online time. Remember, though, that each additional hour costs a hefty $2.95. Spend, say, 10 hours online, and you'll owe $24.70.

You're a casual surfer. What if you do more than send e-mail but you're still only an occasional Web visitor? Again, you don't have to pay $19.95 a month. Provider MindSpring (888-677-7464; www.mindspring.com), which gets an above-average connection rating from Inverse Network Technologies, charges $14.95 a month for 20 hours (and $1 for each additional hour). You'll pay a $25 start-up fee, however, so it takes about six months to beat a $19.95 unlimited plan.

You're often online more than five hours a week. A typical Internet user spends 9 1/2 hours a week online, according to Forrester Research, a Cambridge, Mass. Internet and technology research firm. Most major national ISPs including AT&T WorldNet, Earthlink, Microsoft Network and Prodigy Internet, charge $19.95 a month for unlimited Internet access, as do the big regionals. Some ISPs, however, will cut a deal if you prepay. Prodigy (800-213-0992; www.prodigy.com) charges $189 for a year's worth of unlimited service, which works out to $15.75 a month. And Erol's (888-463-7657; www.erols.com), which serves the Northeast, charges $191.40 for the year, or $15.95 a month.

In addition, small regional ISPs often undercut the big national players. If you live in the Chicago area, for example, you can go online all you want for $14.95 a month with ChicagoNet. For a low-cost provider near you, go to www.thelist.com, which lets you search a list of 5,000 or so ISPs by area code. But remember, if you go online when you travel, you'll want to stick with a national ISP with access numbers throughout the country.

You need fast access. Heavy Internet users know price isn't everything. A reliable connection is. A recent poll by the San Jose-based Internet research firm World Research found that users' biggest complaint was "slow log-in." Unfortunately, your ISP may not help here. "Most people blame their ISP, when it's really the Internet," says Nathan Garcia, co-host of the syndicated radio show On Computers.

You can do something about the second most common complaint: "too many busy signals." What you want is a low user-to-modem ratio: 12 to 1 or less. Regional providers tend to have better ratios. Since you may have a hard time getting that number from the ISP itself, check out Inverse Network Technologies call-failure ratings at www.inversenet.com. One national ISP that has snagged an A+ rating from Inverse for all hours in the two most recent monthly surveys is Concentric Network (800-939-4262; www.concentric.net), which charges $19.95 a month for unlimited service.

Finally, another good way to test an Internet service, says Jack Rickard, editor of Boardwatch, a monthly trade publication for providers, is to get an ISP's local access numbers and call during high-traffic times (early morning, late afternoon and Sundays). If you get lots of busy signals, you may have the same problem when you try to log on--and no price deal is worth that hassle.