I don't think the SD card is involved in video streaming...never heard that, haven't seen a setting related to it on the Pearl.
But you should get one anyway:
- Storing pics in the internal memory will take up too much room and you'll have memory issues
- Storing pics on the SD card will allow you to free up 2 MB of memory on the Pearl by turning off "reserved memory" for pictures on the device
- You must have a memory card to take videos
- Memory card gives you space for MP3s and videos
The are so cheap now...Pearl will take up to 8 GB confirmed, but you can find 2, 4, 6 GB cards for very little...
As for good sites, I usually check Newegg.com - Computer Parts, PC Components, Laptop Computers, Digital Cameras and more!
, TigerDirect.com Best Deals - Computer Parts, PC Components, Computers & Electronics
, Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more
, and if you have a corp discount, the pricing in verizon's store is pretty good.