[How do I make the white area transparent?]

Can anyone tell me the simplest way to make the white area of my picture transparent?

[Crisp clean lines?]

That's quite clean already. If you are looking for even softer lines, I suggest you use a larger resolution while tracing. Also, I think a vector graphics editor would do a better job, such as Adobe Illustrator (expensive) or Inkscape (free).

I'll try the larger resolution. I downloaded Inkscape last week and made little progress. Thanks for the suggestions.

[Crisp clean lines?]

I've spent the last two days searching the forum trying to figure this out myself with no avail. I scanned a simple hand drawn out line and used the line/curve tool to trace around it. I thought this would make nice clean lines but it didn't exactly. I tried a number of blurring, outlining and feathering techniques and still haven't gotten the right results. My goal is to use this picture on cafepress so I'd like the lines to be near perfect. Any suggestions?

This is what I've come up with so far. If you can't tell the dog's back is particularly fuzzy.