Here are a couple of tips, if you are on a budget:
If you only need to program S7-300 (not S7-400), and you do not have to set up any advanced network options, then get SETP7 "lite". It only a third of the price of STEP7 "basis".
Get the MPI/Profibus cable with a serial converter or USB converter.
Its less than half the price of the PCMCIA cards, and you can use them in a stationary PC as well as a laptop.
You dont need a memory card "burner". You can write the programs to the memory cards when they are inserted in the CPU while you are online.
If you absolutely MUST own a "field PG", then contact your local Siemens dealer and ask if they have a demo model or something that they want to get rid of at a reasonable price. Chances are pretty good that they have.