What ever you do dont buy the z906, personally auditioned them, they have the worst sound reproduction ever heard in my life, even the meager F&D 2.1 costing around rs1800 are better.
No balance between highs lows or mids just pure noise!!
If you plan to buy Multimedia speakers,
Go with edifier, logitech just keeps the THX certification and sells the products.
The transformer used in logitech will be half of the edifier.
when compare to performance edifier beats logitech in all aspects.
First i thought of buying logitech z5500, but finally purchased edifier s550
38-40k is a good budget. You have a lot of options from Yamaha,Pioneer,JBL, onkyo etc. For instance Pioneer HTP RS32 , JBL Cinesystem 500.
Any of these can be connected directly to your computer.A good sound card will help.
Other experienced HFV members can suggest some good models.
You can visit a shop in your area and demo the equipment.
In 30K you can buy Onkyo 3500, Yamaha 298, Denon 1312XP etc. All are full home theater systems with avr and speakers. Connecting PC is hassle free with AVR and you can enjoy latest HD audio too.