The next big step in the Peoria Public Library expansion process had been reached.  The Library Board of Directors approved the Medina Plains Corporate Park location as the site for a new North Branch.  That's the 6.2 acre piece of property just west and north of the Super Wal-Mart and new Menard's at Allen Road and Route 6.  Library Board President Mike McKenzie is satisfied with the choice.  The net sale price is $1,067,600.  McKenzie says it's the best overall deal of the three finalists.  The Sud Plaza site across Allen Road eas priced at $690,000, but the property would have land preparation costs of about $700,000.  The North Point location on Knoxville Avenue included a building and parking lot but the sale price was $2,250,000. McKenzie says the contracts will be in the seller's hands Wednesday.  The location will be re-zoned from industrial to commercial.  Then, the next step will be to select the architects.