To start, you should maybe look up for the latest literature regarding your study model and the miRNAs you are mentioning.
If you have already done so (or there is not too much information about your species), you may perform a target prediction based on related species with some of the many online tools that are available nowadays.
For animals, I can recommend you these two:
http://www.microrna.org/microrna/getMirnaForm.do
http://www.targetscan.org/vert_72/
And just in case, I leave you the complete list of tools related to miRNAs that can be useful for you in the future. You have plenty of filters to apply: