Here is something provided by Ron, but we are uncertain as to when this came out. It appears to be a Spanish-language newspaper article promoting a tryout, possibly in 2009.
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In early April 2007 the CBL hosted an open tryout in Dallas for prospective players to make the 4 teams that season. We found a Wayback Machine (archive.org) snapshot of the Bay Area Toros website which lists the original press release issued by the league. The link to that snapshot is here: 2007 Continental Baseball League draft Dallas Texas
We attempted to make a PDF of this release, but the Archive.org snapshot header cuts off some of the list. You are still welcome to see that PDF here: 2007 CBL original tryout and draft PDF
Found some mentions of a September 2009 CBL tryout at Cabrillo College. Here is the PDF flyer:
http://www.cabrillo.edu/academics/athletics/baseball/documents/CBLTRYOUTFLIER2.pdf
Here is a mention from Santacruzlive.com:
If you know of prospective players looking to be informed of independent pro baseball tryouts in 2018 and beyond then have them sign up here: http://www.independentbaseballtryouts.net/