Of course you can. Set it as a profile question, then select "web address" from the "Answer Type" drop down menu. You can set as many as you want.
Yes you can do that, or if you have too many questions already, you can help them post it in a text box and/or one of the "long text" questions.
Thanks to you both! I thought of the "Profile Questions" idea also but would like to have the icons / logos showing. And a Text Box, definitely- I don't know why I did not think of that!!