do you have stratum changed to yes?
For a rig buy AMD 7950s and I would say 4 GBs of RAM and a cheap processor. Use CGMiner. Get PCI-Express Risers to separate the cards or else they will get hotter next to each other. For example my motherboard has 3 side by side PCI-Express slots. When the cards are seperated I get ~67c per card with the fan at 54% when I don't use risers I get 75C
To buy bitcoins transfer money to btce
https://btc-e.com/ using a service in the finances panel after signing up and the buying is straightforward right on the home page, type in how many you want to buy.
3x 7950s would be roughly 750 watts to 800 Watts including everything used for a PC except for a screen. They hash at an average of 550 x 3 hashes with LTC and lets say .14c a Kh/s = $167.34 profit a month after paying electricity, this is the same for LTC and BTC.
Dont forget to join a mining pool and they usually have a pool fee of 1%-5%
Calculate your LTC/BTC mining profit:
http://ltc.kattare.com/calc.phpMore specifically for BTC Profit Calculation:
http://www.bitcoinx.com/profit/snapshot of profit calculation:
http://gyazo.com/bf94efde0be2d0a40ca8b90444aca28a