For deploying sp's (which are located in a script called C:\mySP.sql) you can use:

SET @mySQL = 'CALL isql -S' + @InstanceName + ' -E -i"C:\mySP.sql" < and the rest of your isql options>'

EXEC sp_executesql @mySQL

Ofcourse this only works if the file is located on your machine hosting SQL Server. If you're working remotely (as most people are) you can put the "CALL isql"-commands in a temp-table, select all rows from this table and put them in a batch-file:

CREATE TABLE #tmp (cmd VARCHAR(4000))

-- Do the following for all your instances

BEGIN

   INSERT #tmp (cmd) VALUES ('CALL isql -S' + @InstanceName + ' -E -i"C:\mySP.sql" < and the rest of your isql options>')

END

-- when you're finished

SELECT cmd FROM #tmp

-- Paste the result in a *.bat file and execute it

Grtz, Lex