If I am an American citizen, how long will it take for my spouse to become a resident?

The process is currently taking about 9-12 months for a spouse of a US citizen to qualify for an immigrant visa through consular processing.

You can file an I-130 relative petition for her which will take about 4-6 months. The petition should indicate that she will apply for her visa abroad (since she is in China). Once approved, US Citizenship and Immigration Services (USCIS) will send it to National Visa Center (NVC) for processing of visa. Since you are a U.S. citizen, a visa number is immediately available to her, so NVC will immediately start processing her visa application (about 6 weeks from the time notification of transfer from USCIS to NVC). The visa processing will take about 4-6 months at NVC level (assuming your wife is able to produce required documentation without delay), after which it will be forwarded to the appropriate US embassy/consulate in China for interview. If there are no issues (criminal record, substance abuse, name check hit, previous overstay, communicable disease, etc.), she should be able to get her visa in less than 6 months after completion of the NVC process.

Normally, 6-18 months

You have to file a petition first, it will take about 6 months to get that approved. Then you will have to file all the necessary paper work with the National Visa Center. The whole process can take 8-9 months.

If you commence by first filing a Form I-130 petition, this will take about 8 months. Subsequently, you will contact or be contacted by the National Visa Center "NVC" for consular processing at a US post in China. This additional process may take an additional 5 -6 months. You will be better of seeking the advise of an immigration attorney

You should petition immediately. The sooner, the quicker you will have your wife here. Normally, if all documented are submitted properly, it should take on average up to 6 months. However, it all will depend on the processing. In any way, to sit and keep asking those questions and doing nothing will not expedite bringing your wife here.

Once you file the necessary forms and paperwork, it usually takes between 6 months and 1 year for the final interview and a decision on the green card.

From 8 months to a year from filing of I-130.