CleverGirl
Super Freak
If you can stretch your budget you may want to join the Hot Toys line for some very cool Alien and Predator pieces.
Other than that, Palisades Alien pieces on eBay are cool.
I would love to do a Hot toys Alien, but they are SO EXPENSIVE! I could always save up for a few months... I DID find this Predator lot on craigslist the other day:
They are priced a little high (compared to eBay) but since it's cash I could probably talk the guy down, which one do you think I should jump on? Also if you don't already have them, and there is one you want just let me know I could get it and ship it for you!
Hot Toys Predators for sale
I saw the fully posable NECA 35th Aliens Queen before Christmas for $80 at FYE and REGRET not buying it...
eBay/Amazon wants almost double and higher (after shipping) and Toys R Us/FYE are sold out