All Toyota/Lexus are admissible into Canada from the United States.
http://www.riv.ca/english/US_vehicle_admissibility.pdf

You'll find "How to Import a Car Into Canada" at the Registrar of
Imported Vehicle website. Basically, the cost will be:

1. RIV fee: $195.00 + GST (and QST for QC) plus
2. Air Conditioning: $100.00 + GST
3. GST:  (6%) of total of the purchase price.
4. Duty: Free (confirm that the first digit of the VIN # is 1, 2, 4, or 5).
5. There may also be an excise tax if overweight
6. Inspection fee (Canadian Tire)
7. Provincial Registration fees

North American Automobile Trade Association
Import Tariffs
"Under the North American Free Trade Agreement (NAFTA), vehicles that
are assembled in the United States or Canada do not have any import
tariffs. This is indicated by a 1, 2, 4 or 5 as the first digit of the
VIN."
http://www.naata.org/new%20files/import1.html

Registrar of Imported Vehicle fees
"In order to ensure vehicles manufactured for the United States market
meet Canadian standards, there are several steps to follow.  This web
site explains what you must do.
What to do before you import
What to do at the border
What to do after the vehicle enters Canada
Registrar of Imported Vehicle fees
Numbers you'll need
On-line payment
Frequently asked questions
The fees for the RIV program are:
* Vehicles entering the RIV program with a form 1
  $195.00 + GST and QST for vehicles entering through a port in Quebec
  $195.00 + GST for vehicles entering through a port in any other province
http://www.riv.ca/english/html/how_to_import.html

EBay Motors
Buying a Car from the US - Step by Step
Vehicles Manufactured in North America - Duty Free
All Vehicles are subject to GST - 6%
Vehicles with Air Conditioning - C$100
Vehicles exceeding 2036 KGM - Subject to further excise.
http://pages.ebay.ca/ebaymotors/explained/checklist/howtobuyUS.html

Vehicle Importation from the United States 
For information on the importation of vehicles from the United States,
call the Registrar of Imported Vehicles:
    Registrar of Imported Vehicles (RIV)
    405 The West Mall, Suite 400
    Toronto, ON M9C 5K7
    Within North America: 1-888-848-8240 (English and French)
    Outside North America: 1-416-626-1803
    Internet Address: www.riv.ca
    E-mail Address: [email protected]
http://www.tc.gc.ca/roadsafety/importation/impusae.htm

Ontario Inspection Centres
http://www.mto.gov.on.ca/english/dandv/officeloc.htm

Import duties and taxes
"If your vehicle is eligible for importation into Canada according to
both CBSA and Transport Canada requirements, you will have to pay
import assessments which may include duty, excise tax, and the [6%]
Goods and Services Tax (GST). Provincial or territorial sales tax may
apply when you license your vehicle. If you import a vehicle from
outside Canada into Nova Scotia, New Brunswick or Newfoundland and
Labrador, and you paid for the GST of 7% on your importation, you will
also have to pay the 8% provincial part of the Harmonized Sales Tax
(HST) when you license your vehicle.
Generally, you do not have to pay duty on an imported vehicle that was
manufactured in the United States, Canada or Mexico; however, we will
assess duty on a vehicle manufactured in a country other than the
United States and Mexico. Duty and taxes are assessed on your
vehicle?s ?value for duty?. This is a value determined in accordance
with the Customs Act and declared in Canadian funds. A value for duty
must be established for all goods entering Canada.
Ordinarily, the value for duty is established under the transaction
value method, one of six legislated valuation methods. This method can
apply where there is a price paid (or to be paid) in the sale of a new
or used vehicle for export from a foreign country to a purchaser in
Canada. The price of the vehicle will include amounts for any foreign
sales taxes collected by the vendor, as well as for any warranty
payment made by the purchaser to the vendor or to any third party
identified by the vendor. Certain additions or deductions to the price
may also be necessary. Limitations on the use of this method may
apply.
For example, if the negotiated price of a new automobile is made on a
trip outside Canada, the trade-in value of your old vehicle is taken
into account. In cases where value for duty cannot be established
under the transaction value method, it must be made under one of the
five alternate methods.
For assistance in establishing a value for duty for your vehicle,
contact our Border Information Service line at 1-800-461-9999 during
regular business hours.
If your vehicle has air conditioning, you will have to pay an excise
tax of CAN$100. You will have to pay additional excise taxes if your
vehicle weighs more than 2,007 kilograms or 4,425 pounds. The
following example shows a breakdown of the customs duties and taxes
assessed on a United States-manufactured automobile sold for export
from the United States to a purchaser in Canada and imported in
calendar year 2005.
Example 2005 model year automobile purchase price (includes state
taxes) US$50,000.00 value for duty (price converted to Canadian
currency at current rate of exchange ($50,000.00 x 1.20*))
CAN$60,000.00 duty at 0% $00.00
excise tax on air conditioner 100.00
excise tax on excess weight 00.00 $100.00
$100.00 value for tax (value + duty + excise tax) $60,100.00
GST ($60,100.00   7%) $4,207.00
total cost $64,307.00
total duties and taxes paid to CBSA $4,307.00"
http://www.cbsa-asfc.gc.ca/E/pub/cp/rc4140/rc4140-05e.pdf