Why don’t you get the whole bottom bracket? Here is one I bought from Amazon:
http://www.amazon.com/Shimano-Square-Bottom-Bracket-68x113mm/dp/B005DTIKQE
The size to order consist of two numbers. The first number is the bottom bracket housing length, to measure it, turn the bike over, and measure the frame width at the BB. For example, if the frame color is blue, only measure the blue area and not whatever extends beyond it. The second number is the overall bottom bracket length, which includes the square piece that the cranks fit on. This means that you have to take off your current bottom bracket to measure it.
The special tools needed cost $30, or take it to LBS which usually charge $20 for bottom bracket replacement, and they sell it for $30 to $40. Here are the special tools that you need to replace square taper bottom brackets:
1 – Crank puller:
Park Tool CCP-22 Crank Puller for Square Taper Cranks:
http://www.performancebike.com/bikes/Product_10052_10551_1064837_-1___000000
Spin Doctor Crank Puller:
http://www.performancebike.com/bikes/Product_10052_10551_1030376_-1___000000
2 – Bottom Bracket Tool:
Park Tool BBT-22 Bottom Bracket Tool
http://www.performancebike.com/bikes/Product_10052_10551_1030506_-1_400136__400136
Spin Doctor Cartridge Bottom Bracket Tool
http://www.performancebike.com/bikes/Product_10052_10551_1030396_-1_400136__400136
There is a third tool needed to remove the locking ring(only if present, an extra $15), but I found that I wasted my money because I could have removed it with a flat blade screw driver edge and a hammer. The new bottom bracket as shown above doesn’t require that tool for installation.
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