The equipment needed for speed skating falls into 2 basic groups, mandatory and optional.

Mandatory

• Hard shell helmet (bike or speedskating).
• Skates of course.  Real speed skates start at $250.00 or so but used equipment can be found for less.  Speed skate blades used in short track are 16"-18" in length and are bent slightly (called radius) to the left and are slightly curved (called rocked) to facilitate the turns at high speed.
• Gloves and knee pads (both can be inexpensive).

Optional

• Sharpening Jig and sharpening stones.  Speed skates need sharpening like all skates and most people do this themselves.  Commercial sharpening done at rinks for hockey or figure skates will not work as speed skates have very thin blades (1.1 mm in thickness) and do not have the groove that hockey skates do.  The cost of a basic setup is $125.00.  Often some club members will sharpen skates for the new people. 
• Lyrca tights or similar outerwear make skating much easier as this material does not restrict your movement.
•  Blade covers for storage and blade guards to walk in.

Here is a link to Backstreet Inline Skates which explains the sharpening process

Skate Sharpening