Hi There,
I am new to AIX. I am eager to learn the AIX System administration or if there is any other prerequisite before this. Please can anyone help me or guide how to start with AIX, what all courses and certifications do I need to do. I have basic knowledge of UNIX.
Please guide as I am planning to take this as my career goal.
---------- Post updated at 09:05 PM ---------- Previous update was at 12:10 PM ----------
Is anyone available in this Forum who can guide please ?
What do you mean with "guidance"? Do you want to be a good UNIX administrator? First thing you have to learn - is to learn how to learn. There are a lot of good books and how-tos in the Internet and a lot of information in this forum too. The only man in the world who can help you with all this stuff is you. Read, try to understand, ask a question. Buy some book, e.g. Nemeth's UNIX Administration. It has nothing to do with AIX, but will give some understanding of UNIX to you. Try to find junior AIX position in your country/city. Read IBM Infocenter, read IBM redbooks on topics, which are close to your duties, and on topics, which are interesting to you. Speak with fellow AIX administrators. After year or two you'll probably be ready for AIX Administrator certification (if you need it).
At some point you are going to want to get some time on IBM Power hardware running AIX. Make sure you do your homework on the different Power (5,5+,6,7,8..) systems, their capabilities and their requirements.
Some systems (e.g. 9133-55A) can require either 120v or 220v depending on how many processor cores are installed. You can't just take one processor card out and hope it will work on 120v again! 
Some other things to consider before purchasing hardware:
Again, this is only a factor if your plans are to include purchasing hardware to practice on.
As others have pointed out, the RedBooks are a good source of information, as well as IBM's site (although it changes often enough that some links you find online will be dead - persist and you will find what you're looking for!)
Lastly, with the newer Power systems (P7, P8) more emphasis has been made on Linux on Power. Be prepared to learn about that too if you want this to be your field going forward. 
Cheers,
R