Hi,will you start from Suzhou Railway Station? If so, there are three methods:
first, via white-colored van with "Suzhoulvyoujiaotong" (Suzhou Tourism Transportation) on it. It takes about 1 hour and the ticket is CNY6. Recommended!
second, via highway. takes about 40 minutes and the ticket is CNY10, but the bus looks informal thus not recommende.
Third, a van that takes 6 peopele in total. It won't start until there are 4 people all ready together.

Hi Mr Zellseowck,

I just came back from there about a week ago. i waited for the transportation for almost 1 hour and could not find the tourism transportation. In the end i took a cab which cost me about 90RMB. But on my way back from Tongli to suzhou, i took the bus which cost only 8RMB and it took about 50mins.

The bus station at Tongli is along Yunli Lu. it is about 5 lamp post distance away (to the right if you are facing the town) from the main town entrance(Yunli lu). the station look just like a shophouse. If you didn't go close to it, you won't realise it. The bus is parked behind the shophouse in the day time. Look for for the shop signboard, it is indicated in chinese character.