Dress Shoes
As a teenager, you won't really need dress shoes for any reason besides prom,homecoming, church and other (semi-formal/black tie) events. If you're going to be wearing dress shoes, you'll need to match your suit to your shoes. Black captoes would be a good choice for black suits and more formal events (black is a more formal color). Save these for prom and attending a wedding. If you don't plan on going full formal to prom/homecoming or plan on going to any (technically) semi-formal events, brown wingtips or captoes would be a fantastic choice as well. Since in terms of formality, black > brown, brown dress shoes can be worn more often. Sometimes even casually. If you want to step out of the box, oxblood and longwings would be cool to wear, but be cautious because while oxblood may be worn with just about anything, longwings have their own rules. (Credit to C9B)
Check out MFA's shoe guide for more on Dress shoes.
Where to buy shoes Shoes are often overpriced from the original retailer, so Amazon and Zappos.com are your friends here. You might check out 6pm.com, as they have some decent shoes buried in there for a cheaper price. Don't be afraid to get some off eBay, too. For more traditional shoes like bucks, Desert Boots, and loafers check out thrift stores before ordering online, often your best deals will be from there. Avoid Payless Shoesource, as all their shoes are extremely low quality. On the otherhand, footlocker will often have Nikes and other sneakers that are in good shape. The most important thing is to buy from a well-known brand, as they will generally have the best quality and most durable shoes. That said, if you're looking for some cheap canvas sneakers or Espadrilles, check H&M. They won't last as long, but they'll look good while they do.
Socks
Socks are very important. The most important thing is to steer clear of white tube socks, especially with shorts. Please don't have white socks going to the mid calf while wearing shorts, you'll look like a bit of an idiot. The safest way to go with socks is no-show socks, they're a fashionable choice and you'll have no chance of being ridiculed. Short gray socks are a decent substitute to no-shows. Wool socks and patterned socks are also very cool in the winter. Don't be afraid to just put some baby powder in your shoes and wear no socks at all.
Flip Flops Flip flops are an oft-contested choice of footwear – they're fairly okay in places like California or Florida and are often even considered staples during the summer months, but in most places, they should be reserved for the pool/beach/gym showers and not for standard wear. Basically, use discretion when deciding whether or not to wear them. If you do wear them, make sure you're wearing shorts and are not wearing socks.
footnotes
If I'm missing anything, message me and I'll add it. Please alert me of any grammar / formatting errors as well.
