I cant help with the dynamic pages I am afraid.. It may be worth asking the company that built the e-commerce package if they do an seo add on.

I use oscommerce and that has a great mod that converts the url code into readable text but not sure how that would work with dynamic pages.

I use keyword elite, keyword analyser (great for for PPC) and wordtracker together with KRA pro to find and sort keywords for theming pages.

Keyword elite has a great tool which works well for me that checks the ranking of my keywords. it is very accurate.

I hope that helps.