Easy to remove spaces - however I would remove them from both tables in case there are examples the other way round.
SELECT REPLACE(MyPhoneNo, ' ', '') FROM MyTable
I think this is an example where use of a surrogate key would be well advised (wouldn't you say Teddy? ). Create a tel numbers tables with an autonumber as the Primary Key and telephone number as an alternate key. Then put the primary key number in your other two tables.
At the minimun, if you retain your current deisign, you should be enforcing referential integrity between your two tables to prevent this sort of mees. Easier to type than to impliment I admit however a bit of effort now will save you from this sort of problem again.