Are you keeping track of your submissions?
If you aren’t, you need to start immediately. You should be recording the following information:
Date of submission
Journal name / publisher
Information (link to the submissions guidelines or summary of what to expect and when.)
Result (accepted? rejected? notes from a good submission?)
I keep this information in an Excel spreadsheet. Here are some advantages to using Excel: I can search and find journal names and poem names (much like in a word processing document.) I can sort the entire spreadsheet (by date of submission, journal name, etc.) with the aptly named “sort” function. I freeze the top row so that I can remember what material belongs in which box. With the “filter” function, I can easily find everything in a particular column with a particular word (from a poem or journal title, for example.) For more, About.com has some helpful guides to spreadsheets.
This spreadsheet reminds me if a piece is out for submission (remember that some publications allow simultaneous submissions, others don’t) and its history, as well as my history with particular literary journals. I update it when I receive acceptances or rejections and then resort the spreadsheet so that the submissions that are still pending are gathered together at the bottom.
If you are intent on publishing, your finished work should be in circulation until it is accepted. When you receive a rejection, send the work right back out there (to an appropriate market that you researched first, of course). Remember: Every submission is reason for celebration (see my post Rejection Letters: Cause for Celebration?)