I have been working in the BI space for 3 years now.
As i said earlier, if you are inducted as freshers, you'll be exposed to the basics of most of technologies.
But, if you are really keen on pursuing BI, then would suggest you to get a hang of the basics of 'Data warehousing' (dwh).
Google for Datawarehousing basics and you'll get tons of info. You can also try and understand the differences between ralph kimball vs inmon approaches to dwh.
Also, you can try and understand the differences between an ETL tool (e.g Informatica, Datastage) and a reporting tool (e.g. Business objects, Abinitio).
I'd not suggest you to attend any courses outside at an institute as they themselves dont have much of hands-on. If they have, they'd be working at an IT firm. Not teaching. ;-)
Just kidding, no offense meant to all the trainers out there.
I dont want to dampen your spirits by saying that you might not really have a choice.
But, if you get a hang of the basics then
probably you will have a slight edge over the others and who knows ??!! you might also be able to convince your supervisors in a company to put you into BI.

All the best.
Please PM me if you want any further info.
Regards,
Vikram.