There are many online optical stores offering you cheap nerd eyeglasses.So just search them in the web broswer, like google with key words. A lot of cheap fashion nerd eye glasses will be listed and you will get some reputable online optical stores in the first page. You can compare them to find the most reliable one to get stylish nerd eyeglasses you like best. I know glassesshop.com have a number of nerd style eyeglasses for you to choose. You can see some on their homepage. If you want to get free glasses, go to Coastal to have a look.
Yes, search cheap nerd glasses in Google, you can see there are many places provide you such as Amazon or Ebay etc. Or you can look some online glasses shop like Firmoo, glassesshop and eyebuydirect etc. They offer a number of eyeglasses frames including nerd glasses in low prices. And i saw Firmoo.com offer free glasses, they also carry big nerd glasses. You can go and have a look.