Which Are The Most Reliable And Best Performing Search Engine Optimization (seo) Companies On The Web?

I’m looking to outsource my SEO management. I get a dozen phone calls at my office every day from different companies trying to sell their marketing genious. I am looking for someone to tell me which companies are worth their price and which may not be.

What Is The Most Cost Effective Way To Improve Search-engine Optimization?

Would also be interested in Web hosting and adding flash to our site…again, most cost effective.

Moste Effective Linking Strategy For Traffic?

Hi.
Does anyone have any experience with linking for traffic purposes? (not SEO, though that’s a nice extra).
I’m not too concerned with the SEO benefits…I’m interested in what types of links have brought you the most traffic directly from the links themselves. I’m trying to optomize my time spent here….
Thanks in advance!