I'm doing roughly 1.8MH/s to 2MH/s on my 2 290X cards. Altough I would strongly recommend against buying new hardware for ltc mining now. After the current difficulty skyrocket, you can forget making any reasonable profit, because the difficulty will just keep climbing, while the price will keep falling (was almost 40€ a week ago, is at 21€ now). Alright, I'm sure the price will go up again, possibly into the 1XX€, but thats not a given.
I'm running my cards at standard clock speeds, no OC, fan-speed is unlocked, they run 8 hours a day (when I'm at work, so I don't have to bear with the noise and today I made around .2 Litecoins. 22 Workdays a month a 8 hours makes 4.4 litecoin a month, decreasing rapidly because of the difficulty increases. It's still roughly 100€, but the cards pull 500W minimum, which isn't very cheap.
If you, against all odds, however do decide to get into litecoin mining, get R9 290 cards. They're the most efficient. Try to get your hands on Sapphire versions, they use the best memory (Elpida or sth.) which is most important for Litecoin mining. I would also suggest getting your hands on a beastly powersupply, at least 80+ Gold, if possible 80+ Titanium. Motherboard ->
http://www.asrock.com/mb/Intel/H81 Pro BTC/index.asp with 6 PCIe risers and 6 Dummyplugs. There are two options for CPU: Either a beast of a CPU for other coins (like Protoshares or Primecoins) or a crappy, cheap, low power CPU, that doesn't do anything but run Xubuntu and BFGMiner / CGMiner.
RAM doesn't matter if you want a power-saving CPU, but if you want Protoshares or Primecoins, you need RAM and lots of it. It doesn't have to be high frequency overclocker RAM or anything, you just need the most possible in capacity, altough frequency tends to help.
I'm mining on the pool "hypernova.pw" which has proven to be quite reliable.
For exchanging my LTC into BTC I'm using btc-e.com
And for exchanging my BTC into € I'm using bitcoin.de
WARNING: Keep don't think this is some way to get rich quick. Many have thought that and have failed. Also the Cryptocurrency world is out to get you. There are unbelievably many scammers and I suggest taking EVERYTHING you hear with a grain of salt. Do your own research before trusting people you don't know with anything, if it sounds odd, it usually is.
Have fun and good luck,
Regards, d3
PS:
I forgot to write on topic... Man I'm an idiot
So yes, a friend of mine recently ordered a R9 290 for LTC mining and he got screwed over by the company he ordered from, who increased the prices just after he ordered and then wanted him to pay the higher price, AFTER he ordered for the old price... There's some shi* going down.