Hi there, for readers you can use online systems like
bloglines or one from
google, or propper applications (which i prefer) like the excellent
netnewswire. Personally i'd go for netnewswire, though it costs.
For feeds, there are thousands! Many sites have them, look for small orange logos with curved lines on them, or orange buttons marked rss, xml or atom. In newer versions of safari, a blue symbol marked RSS will appear in the address bar on the right if the page has a feed. Else, go to sites you liek and look around. Personally my feeds (aroudn 100) are a mix of work stuff, webcomics, tech news, apple stuff, literary bits etc etc, and are a mix of normal sites and blogs.
For normal news, i use the bbc feed, but i am a brit. For geeky stuff you can try endgadget, teh register and slashdot perhaps, really it depends what stuff you are interested in.