Re
SEO, you have to be careful. Too many tricks and google will drop your page rank. But, the techniques are as documented as they can be for how to get a higher rating. I do know that one of the key things are links that are in context with where they are linked from. More in-context links, higher page rank. Also what words are used to link to (the words you clikc on).
There have been a few "ask slashdot" type questions about getting a better google result, you may want to search their archives -
http://slashdot.org
There are also some good log analysis tools out there - if you aren't running your own machine, ask your hosting provider to send you logs. I use analog (
www.analog.cx) and have heard good things about webalyzer.
What kind of widgets are you dealing with? Or are you just a middle man for all sorts of stuff? If you can fit into a general area, have you considered running a forum or some other community? Run it on a linode.com virtual server or similar (minimal cost/mo), have banners, etc. going to your clients sites