2004-05: Williams played for Team Illinois in the Midwest Elite Hockey League notching 32 points (14 goals, 18 assists) in 60 games. He was a key player in the team winning the Illinois AAA Title. He was not scheduled to play for Team USA, but he received an invite to join the U-17 team at the Four Nations Cup. He played exceptionally well in the three game tournament by totaling three points (two goals, one assist).
2005-06: Williams played three games for the U-17 team before joining the U-18 team. In those three games he recorded one point (zero goals, one assists) and four PIM. He then joined the U-18 team and played well, recording 15 points (six goals, nine assists) with 59 PIM. He played in 20 games against NCAA opponents and recorded five points (two goals, three assists) with 26 PIM. One of his assists came in a game against his future school, the University of Wisconsin.
2nd round (51st overall), 2006 by COL
Williams attended the University of Wisconsin for only about a month before he left for the OHL due to lack of ice time.
2007-08: Splitting time between OHL Saginaw and OHL Belleville, he helped Belleville reach the Memorial Cup after joining the team via a five-player trade on Dec. 9. He tallied 15 goals and 46 points in 67 games between the two clubs. He tied for fifth among league defensemen in goals and was 15th in points. In 29 games with Saginaw, Williams posted five goals and 19 assists. He notched 22 points and a +16 rating in 38 games with Belleville and racked up a combined 100 minutes in penalties. Williams went on to finish second among OHL defensemen in playoff scoring with 18 points in 21 post season contests. He also recorded three points in four games at the Memorial Cup in Kitchener, Ontario. On Aug. 11, Williams signed an entry-level contract with Colorado.