Pick a player you want, then go to "Make Offer" under "Actions" on the player. Make a loan offer (must be 100% wages and one month). If he joins on loan, put him in the youth squad. Then, select "Actions" and approach to sign him. He will then sign on a free transfer.
To get good players for cheap and you are in a low league, check out the non league teams in Spain. Here you will find good players for cheap. However, occasionally the board of the team who you are trying to buy a certain player from will cancel the transfer, as they will claim that the squad is not big enough. You may need to swap some youth players to buy some of the good players to improve your team.
The following are the best players in the game: GK PLAYER - CLUB Victor Valdes - FC Barcelona P.Cech - Chelsea C.Kirkland - Liverpool DF PLAYER - CLUB Felipe WB/MLC - SC Internacional Rodriguez FB/DLC - Villareal CF J.Carragher FB RLC - Liverpool L.Baines FBL - Wigan Athletic Alex Gonzalez DC - Real Madrid
MD PLAYER - CLUB M.Essien DMC - Lyon Xabi Alonso MRC - Liverpool S. Gerrard MC - Liverpool F.Lampard MC - Chelsea Joaquin WG RLC - Real Betis Fabio Santos WB/MLC - Sao Paulo FC FC PLAYER - CLUB Adriano SC - Inter D. Cisse SC - Liverpool W.Rooney SC - Man Utd M. Owen SC - Real Madrid M.Baros SC - Liverpool Jo SC - Free Transfe