Before you go out and ogle at all the latest and greatest HT gear out there, consider taking some time to figure out exactly what you need.
Don't Forget The Cable
Most people leave cables as a secondary item and instead, max out their budgets
on the actual gear without regard to how your going to connect it. Speakers need
speaker cable, audio components need audio cable, and video gear needs audio and
video cable.
Good audio cables cost at least $20-$60 a pair, good speaker cable is around $1 a foot, and video cable adds another $20-$60. It goes without saying that cable costs can creep up pretty quick, and it is definitely an area you don't want to skimp. After all, your gear's performance is only as good as the cables that connect it.
For info on cables see the On Gear: Cables article.
Where You're Gonna Put It
It might be obvious but the location of new HT gear is more overlooked than cables.
Before you go out and buy anything, you have to be sure you have a place to put
your new gem.
Furniture isn't cheap so make sure you have room for whatever buy.
For info on A/V furniture see the On Gear: Furniture article.
Determining what you need is a small step to take on your road to buying your gear, but it's the most often overlooked. Determining what you need and where it goes early on will save many headaches later when you actually bring that coveted HT component home.