Oh yeah, size has nothing to do with it haha.
and the process, yep you just sign up. So choose your user name and then they send you an email within 24 hours or so, letting you log on. They have to verify things and all so it takes a little while. They give you your password but you can change it afterwards if you like
Then you find a fish you like and you can either bid, you have to enter a Maximum Bid Price, which if you know that the fish most likely isn't going to go much higher in bids, then just bid max at that price. So say the Bid is starting at 15 but the BIN price is 25, you bid for 15 and for the Max Price you put in 15 if you know you're getting the fish. Look at how many page views the fish has had to help determine. Otherwise, if no one has bid yet but the page has lots of views, it might be worth it to do the BIN price.
So then, after you bid or BIN you wait it out and the seller will contact you usually within a day. They will usually tell you your bill and ask you to pay as soon as you can, you can pay by paypal usually just fine. Now if the fish is coming from Thailand, generally you'll have to pay a 2-5 dollar shipping fee; that's to get the fish out of the country and to Hung, your transshipper. Then Hung charges the regular shipping fee to your house which is usually around 30-40? I don't know the exact number since I'm not Canadian. But then I do know he charges and extra 10 dollars PER fish because he can do that, which sucks. Our transshippers don't do that in USA so we're lucky on that part but since Hung is your only transshipper, he does what he wants.
So you pay and voila in a day or two, you have your fish! hooray!
Oh I do note, not all sellers will ask you for that initial 2-5 dollars shipping price, I had two not ask me for it and one did so that was just nice of them ^_^