Tam,
If your running win98 second edition, you can use one of your pcs as a 'gateway' for connection sharing (win98 manual 'getting started' page 83). You will have to buy a hub and some rj-45 cabling (cabling and hub from radioshack or the like, linksys or netgear are good hubwise). If you do get cable or x-dsl I would suggest investing in a router (single port ~$99 again linksys or netgear). It will act as a firewall and dhcp server (still need a hub etc). As for the type of connection to get it depends on what services are available and what your willing to spend. Ideally s-dsl (systemic dsl) is the best (for us) because both download and upload speeds are the same (unlike cable or a-dsl a = asymmetric). While I don't have access to it I'm told that you pay for the speed you want (in incumbents of 192 kbps). I recall someone on PC saying they paid $100/mo for s-dsl at 768 kbs. a-dsl is good for surfing (dl @ 6-1.544 mbps), but can be a PIA for ul (can be as low as 64 kbps, as high as 640 kbps again bucks and availability). Cable is also asymmetric and it is further complicated buy the number of users on any given node. I'm on a 500 member node with only 23 users. I've seen dl speeds of 2.8 mbps and ul speeds 500 kbps. Unfortunately this is only going to go down if any of my neighbors get connected. Theoretically if all 500 slots were full and on line at the same time dl could drop to 80 kbps and I won't even mention ul speeds (5 kbps). Hope that helps.
Mark