as i said before...
as suggested, for us to help you, it would be far better for you to upload a sample workbook. i have a feeling that the way you are doing this, you are ending up with a text answer, rather than a value (currency) answer.
if all you want to do is add the symbol to the value, try this...
=IF( $D$2 ="USA Dollar", 1, VLOOKUP($D$2,$H$6:$I$13,2,FALSE)&" "&(VLOOKUP($D$2 & " to US Dollar",$T$5:$V$46,3,FALSE))*D7)

if later, you want to use that result in a formula elsewhere, refer to it using this...
=MID(F18,FIND(" ",F18,1),6)*1