You can buy any of the prepaid SIM cards for €2 (to be used as your credit), and buy more credit in any of many places all over Serbia (Telenor shops, money exchange offices, supermarkets, post offices, etc)

Here are the options for buying internet, which you can activate by sending a free SMS to the number 9000, with the word MB 50, MB 250, or MB 1000, depending on which option you wish.

- small (mala) - 50 MB - € 3
- middle (srednja) - 250 MB - € 7.5
- big (velika) - 1 GB - € 14

Only one recharge option of the same kind can be activated within the period of 60 days.

After limit is used, the price per MB is € 0.12.

Traffic is charged per 10 KB.
The price of SMS is € 0.03.
One minute of call is € 0.13.
One MMS is € 0.12.

Send SMS with the word STA to 9848 to check the status of your SIM package.

Check the coverage on http://www.telenor.co.yu/?section=private&page=5794

Another exciting information is that you can extend the 60 days validity of your internet package by buying another package. The data allowances will be summed up. This means that if you buy one of the internet packages, and don't use all of it before 60 days has passed, you can extend the left data allowance to another 60 days of validity buy simply buying another package (which must be of a different kind, though).
The same rule applies to the data allowance from the promotion described below. The difference is that the 3 GB from the promotion is not one of the packages, so you can buy any of the packages to extend the initial 3 GB to another 60 days, and then another 60 days, etc etc...