I have always stayed far away from apparel when considering an ecommerce business. My main reluctance stems from how to handle returns. Who pays for the shipment back to you or your supplier? Who pays to ship it out again? If you pass those costs down to the customer, how do you charge them for it? Will the customer want to buy if they know it might cost them more to return something than to go to the local mall and buy something similar?
My wife is (ahem) an avid shopper. I bet you more than half of the clothes that she buys get returned because they don't fit right when she gets home (this is after she has tried them on in the fitting room at the store). She'd probably return 90% of the things she bought online (which she doesn't do, thank goodness).
Oh, and there are no margins at all on electronic goods. Your time and effort are worth more than the measly profts in that niche.