The $100 - $150 Android tablets are Chinese junk. Most of them are using Android 1.6 or older versions and many don't have access to the Android app market.

The Android market is about to heat up, and it's about damn time as waiting for a good Android tablet is getting old. I've seen Android 2.2 running on a 7" tablet and everything is fine even, actually beautiful, though some say Android 2.2 isn't meant for tablets. Basically, Froyo isn't "optimized" for Tablets and Google has specific requirements for tablets only which will be more in line with Gingerbread and Honeycomb (Next versions of Android). The tablets that do come out with 2.2 will need to meet certain minimum requirements in order to access the app market.

But there are about to be some very, VERY good tablets released with Android on them ranging from $400 - $1,000+ depending on size and what you are looking for.

If size isn't an issue, as in the iPod Touch size is fine for your purposes - I'd just buy that. I don't think you'll find anything as good at that price range in the near future for Android. I think most of the action will be in the 7" - 10" range and be a bit pricier.