The phrase "there sits a" is correct and can be used in written English.
This phrase is typically used to introduce a noun in a sentence. For example, "There sits a large oak tree in the center of the park."
On the cover of Curtis Sittenfeld's new novel there sits a frog wearing a crown.
Few people strolling along Sackett Street would guess that behind the worn red brick facade with the weeping cherry out front there sits a sleek modern structure in which everything — walls, floors, the top-floor extension — is brand-new.
SAN FRANCISCO — In the city billed as the gateway to San Francisco there sits a hotel that can claim to being a portal to the United States Open championship.
We like to think that on the window sill of many a little stenographer's bedroom there sits a tiny cactus plant, emblem of horsemanship, love, fresh air, and virtue triumphant.
In the back corner of a spacious living room there sits a bed surrounded by memories of a frozen marriage.
So bring it on home -- the River of the Strait, the mighty Detroit River, flows from Lakes Erie to Michigan, and right there sits a jewel so gorgeous we would be fools to mistake her for dust.
On the looming cliff-face of Dean Clough mill in Halifax there sits an enormous sign, 7m long, in glittering aluminium.
So as you sit there, sit a little longer.
A few blocks from that, there sits an empty flophouse, where thick concrete now caps a passageway discovered by the authorities last year.
On the outskirts of North Braddock, a tiny tree-lined town in the center of Pennsylvania's rust belt, there sits an abandoned 1900s Lutheran church.
There sat a full orchestra waiting for little old me.
