Compiling Problem - Help.

I think it is worth sticking with the 2610.
Once you get the libraries working it is somewhat simple because it only does a few things.

Also, go to Mouser.com and you can download the manual for it.
I just bought five more of the 2610's on Mouser.com for less than a $1 each because they are working well and one of the easier ones to still find.

I had to fix the code for both the .cpp file and the .h file, but here is the code for both of those below.

Hope this helps.

Here is corrected code for the ADNS 2610.cpp file:

/*
 ADNS2610.cpp - Part of optical mouse sensor library for Arduino
 Copyright (c) 2008 Martijn The.  All right reserved.
 http://www.martijnthe.nl/
 
 Based on sketches by Benoît Rousseau.
 
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.
 
 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.
 
 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

/******************************************************************************
 * Includes
 ******************************************************************************/

#include "ADNS2610.h"

/******************************************************************************
 * Definitions
 ******************************************************************************/

#define Delta_Y                         0x02
#define Delta_X                         0x03

/******************************************************************************
 * Constructors
 ******************************************************************************/


ADNS2610::ADNS2610(uint8_t sclkPin, uint8_t sdioPin) : OptiMouse::OptiMouse(sclkPin, sdioPin)
{

}

/******************************************************************************
 * User API
 ******************************************************************************/

signed char ADNS2610::dx(void)
{
        return (signed char) readRegister(Delta_X);
}

signed char ADNS2610::dy(void)
{
        return (signed char) readRegister(Delta_Y);
}

// Private Methods /////////////////////////////////////////////////////////////

Here is the corrected code for the ADNS2610.h file:

/*
 ADNS2610.h - Part of optical mouse sensor library for Arduino
 Copyright (c) 2008 Martijn The.  All right reserved.
 http://www.martijnthe.nl/
 
 Based on sketches by Benoît Rousseau.
 
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.
 
 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.
 
 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifndef ADNS2610_h
#define ADNS2610_h

#include <inttypes.h>
#include "OptiMouse.h"

Class ADNS2610: Public OptiMouse
{
  private:
  public:
        ADNS2610(uint8_t, uint8_t);
        signed char dx(void);
        signed char dy(void);
};

#End If