How does a casual narcissist with no discernible talent rise to the pinnacle of the celebrity-industrial complex without meaning to? In O'Farrell's trite-and-true second novel, all it takes is a small ego problem, a brush with a megawatt star, and an ''epic teenage fantasy.'' At 35, Jimmy Conway divides his time in a dingy English seaside town between a part-time teaching job and putting off work on his screenplay. But when a seemingly harmless lie gets him an invite to the funeral of Britain's biggest TV star, his meteoric rise to faux fame is launched. You won't learn anything from this frothy send-up of our insatiable appetite for the Next Big Thing, but you might annoy the family down the beach with your regular bursts of laughter.