hey buddy .. i am here to help u again
1. see let me break the pricing for u ,
amd 3000+ 64 bit (939 pin) - around 7500/-
asus a8n-e mobo - around 8000/-
there is a cheaper board that u can buy for the 939 proccy but it is a VIA chipset board which sucks big time for gaming and is no match for the nforce chipsets. the model is Asus A8V-E-Deluxe. i dont know the price of this board but i guess it will be much cheaper than the A8N-E.
2. AMD Sempron's are the only 32 bit processors from AMD at present. the best motherboard for a sempron is undoubtedly the ASUS A7N8X-E-DELUXE. Go for the highest sempron model you can find if u want to go for one that is.
3. Ya i own a XFX PCX 5300 and it is a pci express card ... i had bought it for 5k around 6 months back. now i think u will easily get it for around 4k or even lesser. this is a good card if u have a shoestring budget. if u want a good gaming card go for the xfx 6600gt pci express. it will cost around 11k but will be worth the money.
see there is one more option available for u at present which will solve both your graphic card and mobo needs. u can go for the MSI RS480 M2 motherboard which is based on the ati express chipset and has excellent integrated grafix (upto 128 mb share) . this board along with the 3000+ (939 pin) proccy will cost you around 13k. this is a very good buy and decent enough for gaming ,if you are short on cash go for this and see u can alwaz add a grafix card later on this board as it has a pci express slot also. just make sure you have minimum 512 mb ram (1 gb recommended) for this msi board as you will be sharing 128 mb as your video ram.