Federation doesn't get melee weapons in the traditional sense.
Through kits, Federation characters get access to a number of martial-arts moves, all of which are unarmed. If a weapon other than a pistol is equipped, Frds also get to use a rifle-butt as a makeshift club.
Daggers, bat'leth, etc are for non-Federation characters.
I just bought a bat'leth last night for my Vulcan You just have to find the right merchants. I would hint a special space station might have some for sale if you look at the right merchant. And they are awesome. Have to be at least a commander to use them though. But after that they had one for each level.
True, Bat'leths do go for ridiculous prices.. much like most other things.
Sometimes you just get lucky with someone posting a reasonable figure.
That said.. start a Klingon Faction character, make a bit of cash and you can buy them from store (mk IV at 700), I'm sure you'll find ways of getting it to your federation character.