5. Ebay- This tip applies especially for trading card games. Websites like troll and toad have decent prices, but if you have the time and patience to shop around a little, you can find some pretty solid deals on cards. Whether you enter a bid or find a good buy it now, a lot of people on Ebay are trying to get rid of things and wont charge as much as some online retailers.
6. Subscribe- Like comics? so do I. Hate paying $2.99-3.99 for every comic? so do I. Would you like to keep buying comics and save some money? Buy subscriptions! Subscriptions are wonderful and I am a strong advocate for using them. Some shops will give you deals if you subscribe through them, or you can go straight to the publisher. I have 5 subscriptions with DC right now and it is much easier to pay in a smaller lump sum than it is to shell out the cash every week. I still buy some books from shops, but by splitting it up I am able to save some cash and get all the comics I want. Not all companies have the best subscription policy, but DC's is really solid and I assume the larger companies will give a pretty good deal.
7. Research- Know what you are buying ahead of time. This one is simple. Every week I look up the comic release on websites such as comic vine and I see what is coming out. I mark what I plan on buying and then when I go shopping on Wednesday I know exactly what I want. Comic shops and stores that carry nerdy items prey on impulse buys. This way, I know what I am getting and I have few impulse buys. The same idea works for all shopping. Do your research on a new TCG set and you'll probably spend less money on booster packs. If you know when collectibles you want are coming out, you will be able to resist temptation and save money for the items you want.
8. Resist the need to collect- Nerds tend to enjoy collecting things. This can be an issue if you want to save money as there is nothing frugal about collecting things. As nothing in nerding is really necessary, It is hard to tell people to only buy what is necessary, but people can certainly prioritize. You don't need to own everything.