If these investments were made inside an IRA or other retirement account, they are not deductible. If they were not, the post below explains how to record them on your individual return.
You should have recieved a Schedule K-1. This is the form that partnerships use to inform the partners of the tax transactions for the year. Whatever is shown on the K-1 is presumed by the IRS to be the correct amounts for income, deductions, profits, losses, etc.
If you did receive the K-1's, you should enter the information in the K-1 entry screen.
If you did not receive a K-1, you should first attempt to contact the sponsors of each aprtnership and find out if/when the K-1's will be available. If you cannot contact them because they are out of business, you have several choices. 1. File an extension and hope that you eventually get a K-1. 2. Treat the investments as if you did get a K-1 and it showed a loss equal to your investment. 3. Treat the investments as a capital loss with 0 proceeds from sale. 4. Any number of variations of the first three.
The danger in using either 2 or 3, is that you don't really have anything to back up the specific treatment that you choose and the IRS could disallow whatever treatment you use. Depending on the dollar amounts, this could lead to significant penalties.
My suggestion would be that if these were significant investments given your overall financial situation, you should seek competent counsel, a tax attorney or CPA, and have a face to face meeting to discuss the various issues.