First of all, you need drivers if the modem is a software (win)modem. If you don't know if your modem is a winmodem, look at it. Does it have all kinds of chips on the board, or just 1 or 2. 1 or 2 chips means winmodem. These are software driven modems. If you don't have the drivers already, and you can't get on the internet, you're pretty much screwed. What I use for linux is an external modem. Linux is made for external modems. You can pick up US Robotics external modems all day long on http://www.eBay.com
. Make sure you get one with a 25 and 9 pin cable. That's 25 pins on one end, and nine pins on the other.
Linux isn't very fun with dialup, but if you need to use it with dialup, there is a scrip called /etc/init.d/pppd (man pppd from a terminal). If you don't know what a terminal is, CTRL+ALT+F1 will give you a terminal. CTRL+ALT+F7 will get you back where you came from.
If would choose not using a computer anymore before I chose AOL. AOL is a spyware trojan that keeps track of everything you do, whether on the internet of off. You may not care, but there is a lot people can figure out about you by what you do on your computer. Plus, even though AOL won't take your personally identifying info off you computer, they can get your IP, go to your isp's list of users, and see your name, address, phone number, and sell your info to people, who call you, mail you, spam you, and keep track of what scares you.