tedster - 9:31 pm on Sep 28, 2011 (gmt 0)

But what I'm struggling with, is how to be sure, the co occurring terms I'm choosing, are what Google would expect to see.

That's just first date jitters. Or more seriously, if the vocabulary you're adding is clearly related to your page's topic, it's all good.

Yes, the wonder wheel used to be a helpful aid - it really stimulated some ideas for vocabulary expansion. But alas, it is now gone. I heard rumors that it had more scraping hits than real search users.