Hey guys,
Im new to this forum and I'm from a very small island called Maldives where it's impossible to get materials and info.

Can anyone suggest a way to locate and stack aces from a borrowed deck while shuffling ?

Welcome Rahim!
There area two sides of the coin to look at here. First, you've come to the right place for knowledge! On the other hand, unless someone wants to PM you with help, you would have to wait until you reach 50 posts to access the Secret Sessions where magicians and the like can openly share secrets, ideas and advice of this sort. The reason for this is because those secret forums cannot be accessed via an internet search (Google, etc.). We take exposure pretty seriously around here, as I'm sure you can imagine I hope this helps. Again, welcome. We hope to hear more from you in the future!

Rahim,
Such questions have been asked before, essentially what it can boil down to is whether you want to give the perception of locating or stacking the aces during the shuffle or if you actually want to cull the aces during the shuffle.
Personally, and I think a number of people here would agree, the Dad Steven's Cull which comes up sooner in these discussions is next to impossible to get to a game speed for a number of reasons not the Holy Grail (check out genii forum for more on that question).
If you have more flexibility, well the possibilities are fantastic:
- can you spread the cards in your hand?
- can you spread the cards on the table?
- if in the course of a routine with a borrowed deck, can you routine around it?
Admittedly the last couple will be only useful for a magician/gambling demonstration scenario, as well as the Steven's Cull. The gambling side, well read a lot and work out if it's necessary to do so much.

The Stevens' Cull. I can't say you killed me, LoicJ did it last week :p

Arnold,
I thought that might kill you, hence why I added next to impossible to get up to speed (and I would add bending the cards drastically), though it looks as though David Ben believes he could be close
( http://davidben.com/tag/riffle-cull/ )
EDIT:
I'm feeling generous so here is the Genii Forum discussion as well and alludes to why it it pretty much impossible
http://forums.geniimagazine.com/viewtopic.php?t=3701