I just received the bows that I ordered from here:
www.perfectdogbows.com
Although a big pricey, they are WELL WORTH IT! The small bows (5/8") come with two rubber bands. Lexi's hair isn't that long and I put the bands together and only twisted once. They've held for hours so far. I also paid the extra 75 cents for one of the 7/8" bows and had a barrette added to it. There's no way that is going to come out of her hair. Very tight. I might add that these bows are extremely well made. I am truly impressed with the workmanship.
P.S. I like the option of building a custom bow, too. I have a cute little tank top that I was able to match perfectly. I even got to choose what decoration I wanted in the middle of the bow. Oh...the things that make us happy!