Bitcoin API - How can I identify new incoming payments? Good afternoon,

I am struggling a bit to receive Bitcoin payments at my online store. So far, I have installed bitcoind in my system and created a set of receiving addresses, and now I face the problem of checking for new payments.

I am using the following resources: 


https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_Calls_list
http://code.gogulski.com/bitcoin-php/class_bitcoin_client.html


I would like to make a cron job that searches for new payments and stores each one of them into a relational database, each transaction identified by:


Transaction ID
Sender's address
Amount as a 64-bit integer


Everything is pretty easy but I can't find an efficient way of extracting the new incoming transactions from my bitcoin daemon. For instance, I am able to extract the balance of each address, but I don't find a feasible way to obtain a collection of incoming transactions with all required data. This creates a further problem because I don't want to process transactions twice.

Which is the best way to do it using the API?

Thank you very much.
If you want to identify incoming payments, the recommended way is creating a new receive address for every request. When the confirmations of a transaction to a given address get high enough, you can consider the payment confirmed.

Using the 'sender address' does not give you reliable information - it can only identify (one of the) addresses that were previously in control of the coins. There is no guarantee that these correspond to the sender of the payment (it may be a webwallet with shared coins, for example).

Not reusing addresses also has other benefits, like making bitcoins as a whole less easily traceable.