Kmart also have a bit of Generations 2012 (FOC) from time to time and Universe was 5 years ago, so I think you should check online on places like eBay for older figures.

A lot of the old classics/universe figs have gone up in price, some drastically, such as classics Skywarp. If you are looking to get some seekers though, being the original three or the coneheads, I recommend the Ace and Elite Seeker packs, which feature all 3 of each respective team in premium paint jobs, which are quite cartoon accurate.

A lot of online stores, such as BBTS and Robot Kingdom also have most of the generations stuff from 2012 and a few things here and there from the 2010 line and the Japanese United line.

Big Bad Toy Store (great customer service and reasonable prices): http://www.bigbadtoystore.com/bbts/menu.aspx?menu=2339

Robot Kingdom (Reasonable prices, sometimes cheaper, with decent shipping):
http://www.robotkingdom.com/services/eshop/main.php

There are other sites like TFSource and Captured Prey which you might like to check out as well, as most items you won't be able to find at retail (most cases anymore.