After bursting onto the scene as a teenager at Southampton, Bale attracted plenty of interest from Premier League heavyweights.
Ferguson admits United were among those looking to do a deal, but saw an approach knocked back by Southampton.
Shortly after, Bale was on his way to Spurs and, now 23 years of age, he has matured into one of the most dangerous and highly-rated wingers in European football.
Ahead of United's trip to White Hart Lane on Sunday, Ferguson said: "We tried to buy him from Southampton and they turned us down.
"It was not the boy who turned us down, it was Southampton, then a few weeks later he signed for Tottenham.
"It happens. You don't get them all. As I said before, we would have loved to have got (Paul) Gascoigne but we didn't - but we did get Paul Ince and he was a great player for us. These things happen."
On a weekend clash with fourth-placed Spurs, which can be seen live on Sky Sports 1 HD, Ferguson added: "It's an important game because this is a period of the season that if we can keep our momentum going, we have got home games against Everton and Southampton in the next few weeks.
"These are really big opportunities for us."
Tottenham v Manchester Utd is live on Sky Sports 1 this Sunday. For more details click here http://www1.skysports.com/footballonskysports/8395383?DCMP=FootballHub_TotManU_Editorial