Yes. With your experience, it should not be hard for you to learn how to program the Baby Orangutan. In fact, it might be easier than your earlier experiences because you can use the Pololu AVR C/C++ Library to interact with the motor drivers, line sensors, and other hardware. All of our tutorials right now are for AVR Studio 4 but we are working on switching to AVR Studio 5.1 (and then Atmel Studio 6.0 when the final version is out).
Yes. The product page for the 30:1 Micro Metal Gearmotor HP says:
These tiny, high-quality motors are intended for use at 6 V, though in general, these kinds of motors can run at voltages above and below this nominal voltage, so they should comfortably operate in the 3 – 9 V range (rotation can start at voltages as low as 0.5 V).
You can check with our distributors in India to see if they have any of those items available. If they aren't, you can order them directly from us. To see how much that would cost, you can add the items to your cart on pololu.com and go through the first couple steps of the check out process. After you enter your shipping address, our website tells you how much the shipping will cost so you can decide whether to proceed with the order or not.
I strongly recommend getting the Baby Orangutan B-328 instead of the B-48 because I think that you will find the 4 KB program size of the Baby Orangutan B-48 to be very limiting. I compiled the 3pi-linefollower-pid example in the Pololu AVR C/C++ Library, and it takes up 5628 bytes even after I stripped out all the LCD and buzzer code.
Please note that we do not carry any XBee products.