Business Deal Is Over, and Partner Owes Me Money

[graphixx]

First off I hope you can help.
back story: My ex partner owned a business and was expanding this to include a wholesale and an internet portion of the business. I went into this with him and we wrote and agreement stating that I would put up "X" amount of dollars to get the wholesale and internet portion of the business up and running and that I would take a certain % each month as a "partial owner" Well to make a long story short, the wholesale and internet part of this expansion never came into play. The money that I have invested with him was used to keep the retail location afloat well that did not last for long and he went out of business. I did manage to get $2500.00 from him but that is not even half of what he owed me.
he claims that he is not in default which I think is not correct. the agreement we had was for the wholesale and internet expansion of the store and since that never came into play and that my investment money was wrongly used that he is in default and owes the remainder of the investment.

I have been trying for the past 6 months to get the remainder of the money. I have heard every excuse imaginable. I am at my wits end and hope that you good and kind people can give me some guidance as which avenue to persue.

thank you in advance.

[Mr. Knowitall]

Consider small claims court.

[graphixx]

that is kind of what I was thinking this would come too. I was hoping to scare him.
The agreement we had was in writing. and like I said he claims that he was in no way ever in default.
any other suggestions.