Do not purchase aka pre-purchase a BFL asic unless you see in these forums that many people are happy to have received them and are happy with their products.
So far, no one outside of BFL has received anything and have been waiting for months.
Avalon Asic's are decent products but they are out of stock. when available, they cost a fortune on pre-order due to the high demand.
I am not well educated on asicminer to give any details.
If you want to start mining right away and if you want to make it easy, build a PC with minimum 2 PCIE slots, a 700W PSU and a few Radeon Cards such as 5850's, 5870's, 6950's...
refer to the following sites for finding the right videocard
https://github.com/litecoin-project/litecoin/wiki/Mining-hardware-comparison#wiki-ATI_AMD_GPUshttps://en.bitcoin.it/wiki/Mining_hardware_comparisonBefore PC Mining, do your homework on the build's power consumption and your power costs.
If electricity is free, it is very easy to get the hardware paid off within 2-4 months. If it isn't, it might not always be worth it.
Once you have a decent machine, (Should not cost more than 600-1000$ depending on videocards, motherboard and PSU)
I suggest mining for Litecoins as they are more profitable than bitcoins. You can easily exchange them for bitcoins when you have plenty of litecoins. I use BTC-E.com for ltc=>btc and cavirtex for cash deposits to my bank.
