The 22-year-old, capped once by Spain Under-21s, has signed a four-and-a-half year deal after joining from Valencia.
The deal had hit a snag over agents' fees on Tuesday but chief executive Tom Fox managed to complete the move after further talks.
Villa have scored just 11 goals in 21 Barclays Premier League games ahead of Saturday's visit of Liverpool and Lambert hopes attacking midfielder Gil can aid their goal hunt.
He said: "He gives us something we've been crying out for, creativity and spark, we needed that to finish off the work, unlock doors and make things happen.
"We definitely need more (goals)
It's a different culture but he can certainly play football
He's technically excellent so let's see how it goes
He can play on either wing, is really comfortable on the ball and I look forward to working with him.
"It's hard to compare him, he's himself and I can't say if he's like any other player, every player is an individual, we'll try get best out of him.
"I'm not putting massive expectancy levels on him, he's just arrived here but has played in La Liga against great players and great teams
I'm excited by him.
"I don't have any problems starting him against Liverpool
His last game was over a week ago in the Copa del Rey - we'll see how he trains."
Gil also played for Elche for two years on loan from Valencia before returning to the Mestalla at the start of the season and is eager to get going at his new club.
He said: "It's the best league in the world, it's very different from the Spanish league and very difficult
I'm very happy to be able to participate in the league and play.
"They're a big club in the Premier League, a historic club
I'm very pleased to be here
I'm looking forward to training with the team first of all, to get to know all my team-mates and to be in position and ready."
Source : PA