Italian GP 
Scott got his first taste of F1 as a test driver for the Red Bull team, on the Friday of both the Canadian, and United States Grands Prix in 2005.
Debut & Toro Rosso (2006-2007)
Following Red Bull purchased Minardi (became Toro Rosso), they partnered Scott and Vitantonio Liuzzi at the team for the 2006 season.
2006 was largely underwhelming for Scott, perhaps the only note of interest when he had a post-race spat with David Coulthard, for which he was fined $5,000.
2007 was much the same, Toro Rosso never fielded a particularly good car, and neither of the drivers made much of an impression at any of the races. Scott was reported to have an increasingly strained relationship with the Italian team, and unsurprisingly in the end he was replaced mid way through the 2007 season, by Sebastian Vettel.
Speed's best F1 result came in the 2007 Monaco Grand Prix, where he finished 9th. He also finished 9th at the 2006 Austrian Grand Prix (where he had the spat with Coulthard), but only after a 25 second penalty for overtaking under yellow flags.
Post F1
Scott went on to race in NASCAR.