There *is* a V$ view for that, at least in 8.0 and above. Take a look at V$CONTROLFILE_RECORD_SECTION. For example, the following will tell you the current settings of MAXLOGFILES and MAXDATAFILES in the controlfile and how much of those are allready used:

SELECT type, records_total AS max_limit, records_used AS allready_in_use
FROM v$controlfile_record_section
WHERE type IN ('REDO LOG', 'DATAFILE');

HTH,