There are specific telephony cards that work, but are not PnP atm. Using regular modems is something that does not work reliable, IF at all. An external SIP ATA (that's what the SPA is), is the best solution to get regular phone lines into the system. They are fairly inexpensive, and just work.
I've looked around and you are correct, they are not that expensive. One cool thing is that it looks like it may allow me to use VOIP phones in the house to be able to use the intercom features and other telephony features in LMCE. It seems that these phones would be able to touch the outside analogue phone line through the SIP ATA. This is something to think about. Especially since I could run one CAT5 line out to the barn for all my communication needs. Right now, I am going to concentrate on getting my system online. I am still having trouble with getting my MD to boot correctly and also getting my HVR-2250 to work as well. I am going to buy a HDHomeRun-Dual soon but I already had the HVR-2250 so that will have to do for now. Besides, these two issues are forcing me to learn the LMCE system better than if it was flawless from day one. :-)
Thanks for all the advice and I especially appreciate the developers for working on this. I'm looking forward to 10.04.