Have a look here for a bit more info. The song was written by Mark Sheridan, a Music Hall "turn", who also sang it originally. You can get it on compilations. Let's see if I can remember the words from the record:

Lots of folks delight to spend a summer holiday
Down beside the side of the silvery sea.
I'm no exception to the rule, in fact if I'd my way,
I'd reside by the side of the silvery sea.
But if you're just a common-or-garden Smith or Jones or Brown
Who keeps a pub in Town
You've got to settle down.
You save your money all the year till summer comes around,
Then away you go to a place you know
Where the cockle shells are found.

Chorus (and this is the bit where you know the tune!)
Oh, I do like to be beside the seaside!
I do like to be beside the sea!
I do like to stroll along the prom, prom, prom,
Where the brass bands play tiddley-om-pom-pom!
Just let me be beside the seaside,
I'd be beside myself with glee!
And there's lots of girls besides
I should like to be beside,
Beside the seaside, beside the sea!

There's a second verse on MS's record, starting "William Sykes the burglar had been out to work one night", but I've forgotten the rest, sorry. There must have been more verses in the published version, I'm sure; some Music Hall songs must have gone on for ten minutes or more if sung in full - too much to get on a 12" 78.

Who remembers Reginal Dixon at the organ of the Tower Ballroom, Blackpool? OIDLTBBTS used to be his signature tune.

Steve