Hey,
I just spent about an hour trying to get a pdf into autocad 2002. Here's how I finally got decent quality:
First, I opened the page in Adobe Reader (6.0),
then used the "Select All" to get a bounding box around the entire page... then, I changed the zoom to 200 (This is how you can retain the quality). You can paste the image that's now on the clipboard directly into AutoCad, but I found that it took a very long time to process the paste, so, instead, I pasted into PowerPoint first, and resized. Then I selected the image from PowerPoint and did a copy. Then went to AutoCad and pasted. It acutally came in nice and clear.
I know I probably went the long way about doing this, but I didn't have any of the other programs mentioned by the other folks.
Anyway... hope it helps.
Karole