Havent had any troubles here.
Who do you use for an ISP?
I know some of the cable companies have DNS issues sometimes (which could lead to timeouts). As a test, you could try using:
http://www.opendns.com/
Some do not like them since if a site is not in their dns they will redirect you to a page with text ads on it (no popups or anything like that), but their service does work well if your ISPs DNS is screwed up.
Give it a try and see if it fixes your issues :)
EDIT: Forgot to say, to see if it is DNS giving you trouble, try going directly to the IP of the site. If your problem is DNS, going directly to the IP should make it so you have no problems at all (no timeouts):
Earthlink.net:
http://207.217.125.95/
Docsboard.com:
http://209.123.97.165/forums/mainpage.php
Websudoku.com:
http://66.39.22.227/
Some of the pictures and such may not load exactly right, but you should still get to the page and see some of the text from the page.