Thinking of jumping to analog...which turntable?

Given the quality of the rest of your system, it makes sense to invest in a good quality TT / tonearm / cartridge combo. For the money, I don't think you can beat the VPI Scoutmaster, which comes equipped with the JMW-9 unipivot tonearm. The TT, with tonearm, costs $2400 (retail), but if you are comfortable spending a bit more, then you should seriously consider adding the clamping ring (another $600, but well worth the money).

Some good moderately-priced cartridge choices include the Shelter 501, Grado Sonata, Sumiko Blackbird, and DynaVector Diamond 17D (although this is a very low output MC model, so you might need a step-up transformer).

Agree with Sdcampbell on this recommendation. You'll still need to add a phonostage, so this leaves room to make a serious investment in that critical part of the analog chain. Assuming you make a good choice in the phonostage, you will have a very good analog front-end that will be very complementary to the quality of your digital.
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Gentlemen, thank you both for your comments. But I think I should rephrase the question a little bit: given my current digital setup, what would be the minimum investment in analog (phono stage, analog front end) that would provide a significant improvement over my digital. I am willing to experiment with analog if that number is not too high, yet if I need 6-7K to improve upon the sound, then I may need to wait longer to make the analog investment.