Well if you're looking in the 30" range I think you should be able to find something. Plasma's tend to be a bit cheaper but I don't know that they go as low as 30", IMO LCD's provide better image quality but they tend to cost more.
Personally I think LCD provides better image quality than Plasma, but in the interest of disclosure I should say that I work for the largest manufacturer of LCD glass in the world... so I'm not exactly unbiased. I'd recommend that you hit a store with both and do your own comparison. Expect to pay more for LCD, and if you feel Plasma gets you the image quality you want you should look at is as a decent option. For the space you're looking at projection probably doesn't make a lot of sense (unless you have a HUGE bedroom

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