Spain's best-known wine region is Rioja. A relatively small area nestled between two mountain ranges in north central Spain, Rioja produces extraordinary red wines that won't break the bank.
The primary grape in Rioja is Tempranillo which is often blended with Carignane and Grenache. A good Rioja should have dark, plumy fruit with lots of spice and tannin. Riojas with the labeling of "Crianza" or "Riserva" have been aged for a minimum of two years with at least six months in oak, a process which will round out adolescent fruit and makes the wine more approachable.
I don't know much about Riojas, but have been slowly self-educating over the past 3-4 years each time I go to my neighborhood Spanish tapas joints (Cobras & Matadors, Cobra Lily, etc). I've really grown to appreciate them, especially the Riservas. In general, the pricing on these wines is fantastic. And, lucky me, Trader Joe's just started carrying a few Spanish Riojas.
[PS A few weeks back, discovered this really good French Bordeaux at Trader Joe's for $4.99 a bottle.]
Trader Joe's has some of the best cheap wine - great if you are entertaining on a budget.