Yes, you need an arduino set up as a receiver at the PC end.
Range is probably affected by the voltage you are able to supply at the transmitter end also, and whether you have antennas.
See page 3 here as an example of the transmit power difference with VCC change.http://www.sparkfun.com/datasheets/Wireless/General/MO-SAWR.pdf
Seems like the sparkfun summary really disses the General Rx/Tx modules.
Wasn't very difficult at all to use VirtualWire library examples to send data from one place to another.http://www.open.com.au/mikem/arduino/VirtualWire.pdf
No, it won't meet the original poster's request for 300meter & 9,600 baud. But can still be useful.