join results as one column

CAST the account number (assuming it's numeric) as a varchar, then you can concatenate the varchar number and description into one column

select CAST(Distinct((LEFT(RIGHT(GLTran.Sub, 20), 3))) AS varchar(max)) + ' - ' + Account.Descr as account
from GLTran
INNER JOIN Account ON GLTran.Acct = Account.Acct
where GLTran.Acct >= '40000' AND GLTran.Acct < '50000' order by SubAcct asc

got an error:

Incorrect syntax near the keyword 'as'.

CAST(Distinct((LEFT(RIGHT(GLTran.Sub, 20), 3))) as varchar(max))

If this value is always three characters than replace varchar(max) with char(3).

This may also work..

select Distinct(CAST(LEFT(RIGHT(GLTran.Sub, 20), 3) AS varchar(max))) + ' - ' + Account.Descr as account
from GLTran
INNER JOIN Account ON GLTran.Acct = Account.Acct
where GLTran.Acct >= '40000' AND GLTran.Acct < '50000' order by SubAcct asc

Since I don't have access to your data source there's no way I can validate if Distinct((LEFT(RIGHT(GLTran.Sub, 20), 3))) is correct, so you're on your own on that one.

minor change:

select Distinct(CAST(LEFT(RIGHT(GLTran.Sub, 20), 3) AS varchar(max))) + ' - ' + Account.Descr as account
from GLTran
INNER JOIN Account ON GLTran.Acct = Account.Acct
where GLTran.Acct >= '40000' AND GLTran.Acct < '50000' order by GLTran.Sub asc

error:
ORDER BY items must appear in the select list if SELECT DISTINCT is specified.

order by 1 worked!

Thanks for the grade.  Good luck with your project.  -Jim

>order by 1 worked!
If you're SELECTing a lot of calculations, you can ORDER BY the position of the column (1, 2, 3, ...) instead of having to re-calculate.