If you lost your usb cable that came with your camcorder, you may have to order it from the manufacturer, or you might be able to find one at a computer store, but take the camera with you. Out of my 5 cameras, I have three different cable types. It isn't a one size fits all solution.

As for your usb ports, you have as many as are on your pc. You may have 2 - 4 on the back, and possbily some on the front. What you see, is what you get. You only need one available connection to transfer from your camera to your pc. You need to find out if your usb connection is USB 2.0 If not, you may want to see about a firewire connection. You only need a microphone if you want to dub sound onto your movies. If so, do a search here, and on www.dvdrhelp.com and you will get good information concerning which microphone(s) are good and how much they cost.