Let's say $5 to $50.
I'm somewhat particular to red wines. And more specifically, Chilean wines. So this post will be exclusively Chilean wines (I'll make another post on U.S. wines).
In that price range, here is what I'd recommend trying:
Casillero del Diablo by Concha y Toro ~$10. This is a good all-around wine, but it should be breathed. Upon proper breathing, this $10/bottle wine turns into a $20/bottle wine. Also, not only is Concha y Toro the largest vineyard in Chile, it's the 3rd largest in the world, so it shouldn't be too difficult to find this in wine shops. I'm particular to their Carmenere.
Primus The Blend ~$15 A Chilean Bordeaux Blend.
Cousiño-Macul Antiguas Reservas ~$20
LaPostolle ~$20 - $75 Very unique vineyard in that the none of their wine goes through any pumps in that the building is built into the side of a hill wherein the grapes are brought to the top, and the entire process uses gravity to go from vat to bottling.
Perez Cruz ~$20 This is a smaller vineyard located about 45 minutes outside of Santiago, Chile. I've never had a bad bottle from Perez Cruz.
Marques de Casa Concha ~20 One of my personal favorites, primarily because it is easily found in a lot of wine shops. Also, the main vineyard is located on the outskirts of Santiago, Chile.
BTW, I've toured/visited the vineyards where each of the above wines are made.