SuperBiz [ewiz.com] has the incredibly fast SSD by Super Talent for the Dell Mini 9 & 12 [ewiz.com] for $49.99 with free shipping and $5 off with coupon code 5OFF20. There is an additional 5% off through Bing.com's cashback [bing.com].

Product Info:

Specifications
o Mfr Part Number: FEM16GFDL
o The Half Mini 2 PCIe SSD is an upgrade module specifically designed to be a drop in replacement for the Dell Inspiron Mini 9 netbook PC
o Capacity: 16 GB
o Interface: Custom IDE/PATA
o NAND Flash: MLC
o Operating temperature: 0°C to +70°C
o Performance:
+ Sequential Read Rate: 80 MB/s (max)
+ Sequential Write Rate: 40 MB/s (max)
o Power Supply: 3.3V ± 5%
o Dimensions: 30 x 51 x 3.5 mm
o with Super Talent’s 2 year warranty

Customer reviews from Newegg.com [newegg.com]

They have another SSD by Super Talent [ewiz.com] which is also compatible with the Mini 9 & 12 but much slower (Read: 40MB/s Write: 15MB/s). I was considering getting this model last week when it was about $20 cheaper but not now with the faster drive's price drop.

Added note:
If you are looking to upgrade the memory in your Mini 9 the max is: PC2-6400 (800MHz) for speed and 2GB for size. SuperBiz has a 2GB PC2-6400 notebook ram [ewiz.com] for $21.99 with 5OFF20 coupon, plus free shipping. The coupon is a one per customer code, but I did use it twice by logging out of SuperBiz's site and logging back in as a new customer (only had to change my email address).