to check locking scheme of 1 table:

1> use DBNAME
2> go
1> select lockscheme("table_name")
2> go

or

1> use DBNAME
2> go
1> sp_help <table_name>
2> go

To check locking scheme of all user tables:

select "Table"=left(name,32),"lock_scheme"= case
when (sysstat2 & 57344) < 8193 then 'APL'
when (sysstat2 & 57344) = 16384 then 'DPL'
when (sysstat2 & 57344) = 32768 then 'DRL'
end
from sysobjects
where type='U'
go

Sample Output: