HayMeadows - 4:18 pm on Apr 9, 2010 (gmt 0)
Good thread. Haven't seen any comments about the placement of your links on other websites. Going after top of page, higher level, within a detailed write-up, etc.
When exchanging links, I have also found it useful to have a PR4, PR3, PR2, PR1 to trade links with like minded folks. Usually gives you some bargaining power.
Leaving testimonials with a link back to your website is a great thing to do as well.