I've been on the hunt for obscure comic treasure for years, and if you're after rare first editions of 'Aquaman', you actually have more avenues than you'd think—just fewer that are reliable. The absolute cornerstone for me has always been auction houses and specialist dealers. Places like Heritage Auctions and ComicLink often list slabbed CGC or CBCS-graded keys, and they provide provenance and condition notes that help you not get burned. I tend to filter for certified lots because once I paid for a raw copy only to find out later it had restoration work I couldn't spot in photos; lesson learned.
Locally, I still hit comic shops and conventions. I once stumbled on an early 'Aquaman' issue tucked behind modern trades at a neighborhood shop—so don't ignore brick-and-mortar stores. Big cons also host dealers who bring rarities, and you can inspect the book in person. For online hunting, eBay is obvious—use saved searches, bid sniping tools if you're patient, and check seller feedback closely. MyComicShop, Midtown Comics, and specialist auction catalogues are safer bets if you want established businesses. Facebook groups and Reddit communities like r/comicswap can be great for leads, but treat them like flea markets: ask for high-res photos, provenance, and prefer tracked shipping.
A couple of practical tips from my mistakes: learn to read grading terms and prefer CGC or CBCS slabs for higher-value purchases; consult the 'Overstreet Price Guide' or ComicsPriceGuide for ballpark values; and always factor in insurance and secure shipping. Also, know the keys: Aquaman's first appearance is in 'More Fun Comics' #73 (1941), so that's prized and often extremely pricey. Finally, patience pays—set up alerts, make a wants list, and be ready to pounce when a legit copy appears. I still get a little jittery before placing big bids; it’s part of the fun.