Google does costantly change its results, especially at the moment wth updates etc being pushed through. You will often find that sites drop down the rankings for a couple of days, and then reappear near the top. The process repeats a couple of times, and then things settle down.
I`m not sure about why it happens, but I wonder if its to discourage the "here today, gone tomorrow" sites that spring up and disappear to try and spam the rankings. By moving the sites up and down it effectively renders them useless. Once your site is proven to be one that is staying for the long term, they leave it alone. Have no idea if this is correct or not, its just my theory, based on whats happened to my own sites
Thankfully I was lucky enough that the flux stopped before christmas for me, and my sites ended up at number 1 in google and stayed there, was fantastic timing, but more to do with luck than anything else.
I do know google does have a bit of a problem with squidoo though. Squidoo has suffered from a lot of spam and useless pages, as its open to everyone, and google had a real problem with this. At one stage they removed all squidoo sites from the index, and I suspect that although they are reincluded, they are harsher on squidoo pages.
To be honest with you though, if you are relying on your pages to make sales, I would host them on something like squidoo thats beyond your control. What would happen if squidoo shut down tomorrow, or decided to wipe their pages and start again? (Ok, its unlikely to happen, but you are relying heavily on them). Its much better to have your own webspace and host your pages there. Gives you more control over everything, including page layouts and
SEO.
Its so cheap now for webhosting, even a VPS is dirt cheap, so theres no excuse really for not getting your own hosting, and it would benefit you in many different ways.