Completely made up words can be tricky - espeically because they may have unfortunate meanings in languages you are not aware of (the "no-va" automobile brand fiasco in Latin America comes to mind.)
There's a process I usually engage, back and forth between available domain name utilities and "words". That process can build momentum as you engage it. I know I can't do it all in my mind - I just start to loose it!
I'll second Tedster on the nonsense words. Without offline branding and alot of it...I think they're usually difficult to remember.
And questions about the origin of your domain name are inevitable, especially by people who had difficulty remembering it previously.
So you might want to think about the kind of feeling you would like to inspire in your site visitor (Gee, that site offers great values), and pick some words that inspire those feelings.
Another way to brand it is by using words that describes your demographic audience (or how they perceive themselves), such as smartkids, sassygal, etc.
I did all the dictionary stuff but ultimately it didn't help. You need to keep coming back to the important issue - what is the brand about?
Beyond that avoid anything generic otherwise, in the case of a domain name dispute, you won't have much of a case.
carphonewarehouse
Ref Mil-Mar Shoe v. Shonac, 75 F. 3d 1153 (7th Cir. 1996): 'Warehouse Shoes' held to be generic for a place where shoes are sold