If money is not an option then consider getting a spell/language checker too
Truth be told, great developers or designers don't need the best tools to create amazing things. But the best tools do help. Perhaps invest more time and money in developing your design technique and skill. If you have to ask which tools to use, chances are there are quite a few useful things you may still need to brush up on.
What hyperian says is true. But if you got the bucks you can perhaps invest in the Adobe Creative Suite 4 Web Premium, although I personally recommend 3 as I've had issues with 4, aaaand if you can afford to wait (sees what i did thar??), chances are 5 will be announced in the next couple months with a release date shortly afterwards.