In photoshop, they have an extract tool in the filter menu.
If you've got a lot of patience to sit and practice, then you'll get the hang of it, but what I'd do (even though I can't see the pics you've got on photobucket), is I'd copy it over to a new file that has the background transparent on the outset (Set it to transparent when you make a new document), then I'd use the different brushes for the eraser to take it out.
Change brushes by right clicking on the picture, then selecting a different brush, click on the size and off you go.
Also, you can change the opacity up the top of the screen to be heavier erase or lighter.
Test all these bits out and with a little patience (or perhaps a lot, I'm not sure what you're working on) you can get the bits you want done.
Hope that helps.