replacing data in excel

i am trying to prepend data to existing data in excel.

the data in the cell is a varying set of numbers.

i want to prepend a character to the data. for instance 123.45 becomes ABC-123.45 the next cell may be 125.24 and become ABC-125.24

the prepend will always be the same.

I have tried find / replace but that will only find data that is the same. i tried find * but it was looking for an *.

i tried using IF statements but it replaced with an *.

I also need to have the data replace into the same cell as this will become part of a program.

any suggestions please.