Palm’s international carrier base for the Pre is growing. Palm’s European carrier partner, O2, announced pricing and availability for the Palm Pre in the United Kingdom, Germany and Ireland.

O2 says the Pre will be available on Oct. 16. Customers can purchase the new device directly from O2, online or from retail locations such as Carphone Warehouse and Phones4U.

In the United Kingdom, O2 will enact a tiered system for pricing, which will depend on the length of contract a customer chooses. The Pre is free to O2 customers who agree to a two-year contract and to customers taking an 18-month contract, the phone will cost £44.05 or £73.41 per month, depending on the tariff plan they choose.

To date, the Palm Pre has only been available on Sprint in the United States. Sprint launched the Pre in June to long lines and limited availability. Since then, reviews of the phone have been generally positive, with some complaints about the Pre’s lack of apps.

However, much to Palm’s dismay, the Pre hasn’t sold quite as well as many thought it would. The OEM recently reported disappointing earnings for first quarter of 2010 and just yesterday raised its stock sale by 25 percent in a move to bring in additional cash.

Palm plans to sell off a minimum of 20 million shares at a price of $16.25 each, a 5 percent discount to Tuesday’s closing price of $17.07. Last week that figure stood at 16 million shares.