If I get inbound links from a high power site, but they make the links no follow links will that at all help me with my rankings in Google/Yahoo?

there is not difference with follow and no follow it just don't pass the Page rank else it does the same job as do follow

But if it isn't passing pagerank than it isn't going to help the SERP the same as when sites ARE passing pagerank, right?

There are a few tests that people have done, to try to answer this question...
For example perhaps see http://www.socialseo.com/blog/an-experi ... oogle.html

Of course you will find others who have tested this (and comments which are helpful) if you hit the search engines

Hope comments are useful - cheers, Asiaplay